The invention relates to an ion detector having a sensing electrode, an evaluating circuit, and an indicator means.
The known ion detectors are measuring instruments in which a blower drives the air being tested between two sensing electrodes to which a given voltage is applied. The deflection of the ions which takes place in the field between the sensing electrodes produces a reactive current whose magnitude is determined in the evaluating circuit and indicated. In this manner the ion density can be measured fairly accurately. The apparatus, however, is very expensive.